In traditional rice cultivation, the fields remain continuously flooded during growing season. The organic matter in the soil (straw, manure, etc) decomposes anaerobically (without air) and releases as a byproduct, methane, a greenhouse gas 25x more potent in greenhouse warming effect than carbon dioxide (CO2).
|Transplanting rice in a flooded field -- hard work!|
In AWD, the water level is allowed to drop to 6 inches below the top of the soil before irrigating again to 2 inches above soil level. This process of drying the soil and irrigating continues until harvest. Since the soil is allowed to dry periodically, the organic matter decomposes with the help of oxygen, preventing methane from being produced.
This practice has proven to have no negative impact on yield; in fact, in some cases, yields increased. Farmers have also reported that the roots have better anchorage (making them typhoon-resistant). Grains also have a good shape and size, with lower trace amounts of arsenic that naturally occurs in rice.
Moreover, AWD practice reduces methane emissions by 50% on average and decreases water use by 30%. It’s a win-win situation for climate change mitigation and adaptation. Not only are farmers reducing their greenhouse gas emissions, but they are also adopting a climate-smart technique which will better prepare them for water scarcity which climate change may bring.
With decreased water usage, farmers save money in cases where they use diesel-pumped irrigation systems. AWD also decreases conflict between farmers since there is less likelihood of experiencing a water shortage.
The main challenge to implementing AWD will be to break farmers’ deeply entrenched belief that rice is an aquatic plant that needs to be continuously flooded. No easy task where almost all the rice fields are cultivated by smallholder farmers with 1.2 hectares each on average and have been growing rice for generations.
However, AWD has been gaining ground. It’s being adopted in China, Vietnam, Myanmar and Indonesia. In the U.S., too! In fact, the world’s first carbon credits from AWD in rice cultivation were generated just last month by farmers in Mississippi, Arkansas and California.
The 5th Mark of Mission of the Anglican Communion guides us in our calling “to strive to safeguard the integrity of creation and sustain and renew the life of the earth.” We can live into this mission wherever we are and in whatever we do, whether we are farmers or office workers. For farmers, this means cultivating the land in the best way possible. For an office worker, it may mean shutting down computers to save electricity, turning off lights, reducing waste and recycling and composting at work. Everyday, we have the opportunity to show thanks to God for the beauty and resources He gives us by being good stewards of His creation. Let’s show it!